def describe_pet(animal_type,pet_name):
    """显示宠物的信息。"""
    print(f"\nI have a {animal_type}.")
    print(f"My {animal_type}'s name is {pet_name.title()}.")

describe_pet('hamster','harry')

def describe_pet(animal_type,pet_name):
    """显示宠物的信息。"""
    print(f"\nI have a {animal_type}.")
    print(f"My {animal_type}'s name is {pet_name.title()}.")

describe_pet('hamster','harry')
describe_pet('dog','willie')

def describe_pet(animal_type,pet_name):
    """显示宠物的信息。"""
    print(f"\nI have a {animal_type}.")
    print(f"My {animal_type}'s name is {pet_name.title()}.")

describe_pet(animal_type='hamster',pet_name='harry')


def describe_pet(pet_name,animal_type='dog'):
    """显示宠物的信息。"""
    print(f"\nI have a {animal_type}.")
    print(f"My {animal_type}'s name is {pet_name.title()}.")

# 一条名为Willie的小狗。
describe_pet('willie')
describe_pet(pet_name='willie')

# 一只名为Harry的仓鼠。
describe_pet('harry','hamster')
describe_pet(pet_name='harry',animal_type='hamster')
describe_pet(animal_type='hamster',pet_name='harry')